Emergency breathing apparatus of this kind are used in emergency situations in modern transport systems and especially in passenger aircraft, railroads and ships and are intended to protect passengers and crew against the consequences of fire and especially from smoke and gas poisonings.
U.S. Pat. No. 5,027,810 discloses an emergency breathing apparatus incorporating a hood which makes oxygen from a pressurized cylinder available for a time duration of approximately 5 to 10 minutes. The central component of this hood contains the pressurized gas cylinder with oxygen, a labyrinth-like configured flowpath through an absorption material and an ejector directly at the outlet valve of the pressurized gas cylinder.